Time-domain interferences as the source of electron-ion entanglement in Rabi-dressed photoemission

TL;DR

This paper explores how time-domain interferences during Rabi oscillations lead to entanglement between a photoelectron and its parent ion, enabling state reconstruction from photoelectron spectra.

Contribution

It introduces a numerical simulation approach to link time-domain interferences with electron-ion entanglement and demonstrates state tomography from spectra.

Findings

Entanglement arises from ionization at different times during Rabi oscillations.

Photoelectron spectra can reveal the purity of the ionic state.

Dressed ionic state dynamics can be reconstructed tomographically.

Abstract

We investigate bipartite entanglement between a photoelectron and its parent ion when the latter undergoes Rabi oscillations, following the recent experiment of [Nandi et al. Science Advances 10, eado0668 (2024)]. Using numerical simulations on a model atom, we show that this entanglement results from ionization events occurring at different times, with the photoelectron leaving the ion in distinct superpositions of internal states due to the Rabi coupling. Our interpretation brings forward the possibility to access the purity of the photoion state from photoelectron spectra. Furthermore, we demonstrate a tomographic reconstruction of the dressed ionic state dynamics from the observable spectra.